Analog IC

What is a power supply?

All electronic and electric devices in the world around us require a power supply to run. To use an analogy, the power supply is like the foundation of a house. However, mostly it is taken for granted and not really given much thought, like air.

Although we use the simple term, "power supply", in actuality the voltage and type of power supply required by devices varies greatly. Well-known power supplies used in homes are AC voltage (the power obtained from wall sockets) and batteries, but practically no devices use these types of power (voltage) directly. Rather, electronic circuits inside each device converts the voltage to one that is suitable for use.

Types of power supplies

AC power supply (alternating current power supply)For example, sockets in homes. AC 100 V is supplied.

DC power supply (direct current power supply)Dry cells (batteries) are the typical DC power supply. Several types of voltage are available: 1.5 V, 3 V, 9 V, and so on. Mobile devices use rechargeable batteries.

Other power suppliesOther splendid power supplies include generators and solar batteries.

What is a primary power supply?

For electronic devices using AC power from a socket as a power supply, it is necessary to insulate the socket and the electronic device to prevent electric shocks. Therefore, AC/DC converters that convert alternating current to direct current use a transformer to insulate both the socket and the electronic device. The power supply circuit of the socket on one side of this transformer is called the primary power supply, and the circuitry in the electronic device on the other side is called the secondary power supply.